package cn.itcast.hotel.service.impl;

import cn.itcast.hotel.mapper.HotelMapper;
import cn.itcast.hotel.pojo.Hotel;
import cn.itcast.hotel.pojo.HotelDoc;
import cn.itcast.hotel.pojo.PageResult;
import cn.itcast.hotel.pojo.RequestParams;
import cn.itcast.hotel.service.IHotelService;
import com.alibaba.fastjson.JSON;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.apache.commons.lang3.StringUtils;
import org.elasticsearch.action.delete.DeleteRequest;
import org.elasticsearch.action.index.IndexRequest;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.common.geo.GeoPoint;
import org.elasticsearch.common.lucene.search.function.CombineFunction;
import org.elasticsearch.common.unit.DistanceUnit;
import org.elasticsearch.common.xcontent.XContentType;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.functionscore.FunctionScoreQueryBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilder;
import org.elasticsearch.index.query.functionscore.ScoreFunctionBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortBuilder;
import org.elasticsearch.search.sort.SortBuilders;
import org.elasticsearch.search.sort.SortOrder;
import org.elasticsearch.search.suggest.Suggest;
import org.elasticsearch.search.suggest.SuggestBuilder;
import org.elasticsearch.search.suggest.SuggestBuilders;
import org.elasticsearch.search.suggest.completion.CompletionSuggestion;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService {

    @Autowired
    private RestHighLevelClient client;
    @Override
    public PageResult search(RequestParams params) {


        try {
            //创建request请求
            SearchRequest request = new SearchRequest("hotel");
            //搜索条件

            SearchSourceBuilder source = request.source();
            bulidBasicQuery(params,source);

           //设置分页
            Integer page = params.getPage();
            Integer size = params.getSize();
            source.from((page-1)*size).size(size);

            //排序
            if (StringUtils.isNotBlank(params.getLocation())){
                source.sort(SortBuilders
                .geoDistanceSort("location",new GeoPoint(params.getLocation()))
                .order(SortOrder.ASC)
                .unit(DistanceUnit.KILOMETERS));
            }

            //sortBy排序
            if (StringUtils.isNotBlank(params.getSortBy())){
                if (params.getSortBy().equals("score")){
                    source.sort("score",SortOrder.DESC);
                }else if (params.getSortBy().equals("price")){
                    source.sort("price",SortOrder.ASC);
                }
            }
            //发送请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            //解析响应数据
            SearchHits hits = response.getHits();
            //查询总条数
            long total = hits.getTotalHits().value;
            //遍历hits
            ArrayList<HotelDoc> hotels = new ArrayList<>();
            for (SearchHit hit : hits) {
                String json = hit.getSourceAsString();
                HotelDoc hotelDoc = JSON.parseObject(json, HotelDoc.class);

                //获取高亮处理结果
                Map<String, HighlightField> highlightFields = hit.getHighlightFields();
                if (!CollectionUtils.isEmpty(highlightFields)){
                    HighlightField field = highlightFields.get("name");
                    //高亮处理结果字符串
                    String highLightResult = StringUtils.join(field.getFragments());
                    hotelDoc.setName(highLightResult);
                }
                //获取排序值
                Object[] sortValues = hit.getSortValues();
                if (sortValues.length>0){
                    Object sortValue = sortValues[0];
                    hotelDoc.setDistance(sortValue);
                }
                hotels.add(hotelDoc);
            }
           return new PageResult(total,hotels);

        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException("es搜索出错");
        }

    }

    /**
     * 构建基础查询条件
     * @param params  请求参数
     * @param source  条件
     */
    private void bulidBasicQuery(RequestParams params, SearchSourceBuilder source) {

        //构建bool查询
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        //关键字搜索
        if(StringUtils.isBlank(params.getKey())) {
            //key为空 查询全部
            boolQuery.must(QueryBuilders.matchAllQuery());
        }else{
            boolQuery.must(QueryBuilders.matchQuery("all",params.getKey()));
            source.highlighter(new HighlightBuilder().field("name").requireFieldMatch(false)
            .preTags("<em>")
            .postTags("</em>"));
        }

        //城市查询
        if (StringUtils.isNotBlank(params.getCity())){
            boolQuery.filter(QueryBuilders.termQuery("city",params.getCity()));
        }
        //品牌查询
        if (StringUtils.isNotBlank(params.getBrand())){
            boolQuery.filter(QueryBuilders.termQuery("brand",params.getBrand()));
        }
        //星级查询
        if (StringUtils.isNotBlank(params.getStarName())){
            boolQuery.filter(QueryBuilders.termQuery("starName",params.getStarName()));
        }
        //价格查询
        if (params.getMaxPrice()!=null && params.getMinPrice()!=null){
            boolQuery.filter(QueryBuilders.rangeQuery("price")
            .gte(params.getMinPrice())
            .lte(params.getMaxPrice()));
        }

        //算分函数条件
        FunctionScoreQueryBuilder functionScoreQueryBuilder =
                QueryBuilders.functionScoreQuery(boolQuery, //原始查询条件
                        //算分函数 数组
                        new FunctionScoreQueryBuilder.FilterFunctionBuilder[]{
                                //算分函数
                        new FunctionScoreQueryBuilder.FilterFunctionBuilder(
                                //筛选条件
                                QueryBuilders.termQuery("isAD",true),
                                //计算方法
                                ScoreFunctionBuilders.weightFactorFunction(10)
                        )
                }).boostMode(CombineFunction.MULTIPLY);  //加权模式

        //放行source
        source.query(functionScoreQueryBuilder);
    }


    @Override
    public Map<String, List<String>> getFilters(RequestParams params) {
        try {
            // 1.准备Request
            SearchRequest request = new SearchRequest("hotel");
            // 2.准备DSL
            // 2.1.query
            SearchSourceBuilder source = request.source();
            bulidBasicQuery(params,source);
            // 2.2.设置size
            request.source().size(0);
            // 2.3.聚合
            buildAggregation(request);
            // 3.发出请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 4.解析结果
            Map<String, List<String>> result = new HashMap<>();
            Aggregations aggregations = response.getAggregations();
            // 4.1.根据品牌名称，获取品牌结果
            List<String> brandList = getAggByName(aggregations, "brandAgg");
            result.put("brand", brandList);
            // 4.2.根据品牌名称，获取品牌结果
            List<String> cityList = getAggByName(aggregations, "cityAgg");
            result.put("city", cityList);
            // 4.3.根据品牌名称，获取品牌结果
            List<String> starList = getAggByName(aggregations, "starAgg");
            result.put("starName", starList);

            return result;
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    private void buildAggregation(SearchRequest request) {
        request.source().aggregation(AggregationBuilders
                .terms("brandAgg")
                .field("brand")
                .size(100)
        );
        request.source().aggregation(AggregationBuilders
                .terms("cityAgg")
                .field("city")
                .size(100)
        );
        request.source().aggregation(AggregationBuilders
                .terms("starAgg")
                .field("starName")
                .size(100)
        );
    }

    private List<String> getAggByName(Aggregations aggregations, String aggName) {
        // 4.1.根据聚合名称获取聚合结果
        Terms brandTerms = aggregations.get(aggName);
        // 4.2.获取buckets
        List<? extends Terms.Bucket> buckets = brandTerms.getBuckets();
        // 4.3.遍历
        List<String> brandList = new ArrayList<>();
        for (Terms.Bucket bucket : buckets) {
            // 4.4.获取key
            String key = bucket.getKeyAsString();
            brandList.add(key);
        }
        return brandList;
    }

    @Override
    public List<String> getSuggestions(String prefix) {
        try {
            // 1.准备Request
            SearchRequest request = new SearchRequest("hotel");
            // 2.准备DSL
            request.source().suggest(new SuggestBuilder().addSuggestion(
                    "suggestions",
                    SuggestBuilders.completionSuggestion("suggestion")
                            .prefix(prefix)
                            .skipDuplicates(true)
                            .size(10)
            ));
            // 3.发起请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            // 4.解析结果
            Suggest suggest = response.getSuggest();
            // 4.1.根据补全查询名称，获取补全结果
            CompletionSuggestion suggestions = suggest.getSuggestion("suggestions");
            // 4.2.获取options
            List<CompletionSuggestion.Entry.Option> options = suggestions.getOptions();
            // 4.3.遍历
            List<String> list = new ArrayList<>(options.size());
            for (CompletionSuggestion.Entry.Option option : options) {
                String text = option.getText().toString();
                list.add(text);
            }
            return list;
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void deleteById(Long id) {

        try {
            //准备request请求
            DeleteRequest request = new DeleteRequest("hotel", id.toString());
            //发送请求
            client.delete(request,RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void insertById(Long id) {

        try {
            //根据id查询酒店数据
            Hotel hotel = getById(id);
            HotelDoc hotelDoc = new HotelDoc(hotel);
            //准备request对象
            IndexRequest request = new IndexRequest("hotel").id(hotel.getId() + "");
            //转换为json数据
            request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
            //发送请求
            client.index(request,RequestOptions.DEFAULT);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

    }
}
